Bark mulch typically comes from milled fir, pine, redwood and spruce logs, notes Clemson Cooperative Extension. Landscape bark mulch is graded according to particle size, ranging from bark chunks or nuggets, bark granules and shredded bark. Bark chunks last the longest and granules are useful for soil conditioning. Bagged bark mulch has usually weathered enough to destroy any toxins that may harm plants. The coarse bark mulches are more effective for weed suppression; seeds can germinate in fine, moist bark mulch.
Garden bark mulch has many functional uses in the landscape, including helping to suppress weeds, although it doesn’t provide an impenetrable weed barrier. It’s an organic form of mulching, conditioning the soil as it deteriorates. You shouldn’t layer bark mulch too deeply or problems with moisture and disease can put the plants’ health at risk.
Garden Bark Mulch for Landscaping
Bark chunks or nuggets are suitable for shrub beds and trees; apply finer granules to perennial and annual beds. Pull bark mulch away from the stems of plants, especially in the spring and for disease-prone plants such as roses — soil is slower to warm in the spring with a layer of mulch on it, and moisture trapped around the stem creates favorable conditions for the growth of fungi.
Bark mulch is used with ornamental shrub planting as a method of weed control. Bark mulch suppresses weeds by blocking light that seeds need to germinate, but it doesn’t completely prevent weeds. It also helps retains moisture in the soil and keeps plant roots cool in hot weather. Bark mulch resists compaction, it doesn’t blow away and it provides an attractive finish to newly planted areas. It’s also a by-product of the lumber industry and so readily available.
Mulch Depth to Prevent Weeds
To determine how much mulch you’ll need for an area, use an online mulch calculator. You’ll need to know the width and length of the project area to determine the square footage of the bed you plan to mulch, along with the depth of mulch you want to apply to the area.
All of our bark products are supplied in 1m3 bulk bags. One bulk bag will provide approximately: 20m2 coverage at a depth of 2 inches (50mm), 13m2 coverage at a depth of 3 inches (75mm), or 10m2 coverage at a depth of 4 inches (100mm).
Suppresses Weed Growth – Bark shades weed seeds from the sunlight they need to grow, and allows your desirable plants to receive the soil, water and nutrients they need – without undue competition.
We recommend laying bark 2-4 inches (50-100mm) deep. For finer barks such a composted bark, 2 inches is sufficient. For coarser barks such as bark nuggets, 3-4 inches may be more beneficial. Be careful not to lay too thickly as this can deprive the soil and plant roots of oxygen; or too thinly, as this will increase the soil’s exposure to sunlight and may hinder weed control.
How much bark will I need?
Yes, a soil with good structure will have a soil atmosphere – air space between soil particles. Because our bark has an open porous structure, contact between the ambient air and the soil atmosphere is maintained and the soil can breathe as normal.
There is a significant amount of experimental research showing the inhibition of a number of plant root diseases when using composted bark – these include Rhizoctonia, Pythium, Phytophthora, Tomato Root Knot and Forsythia Parasitic Nematodes.
Does bark kill weeds?
To work out how many bulk bags you need, simply multiply the length, width and depth of your area in metres. For example: 4m (length) x 5m (width) x 0.05m (depth) = 1m3 (1 bulk bag).
Retains Soil Moisture – Bark softens the impact of rain water so that it can effectively permeate the soil, and significantly reduces evaporation from the soil surface.
If weeds start popping up in mulch, we want to tackle them before they can seed and spread. If you’re pulling weeds by hand, make sure you get the whole weed, including the root. Applying a pre-emergent herbicide is also an option. One approach is a commercial weed-killer like Roundup, which contains the chemical glyphosate. Some gardeners prefer a more natural approach, using a mixture of vinegar, salt, and dish soap to kill weeds as they grow.
We all know how tenacious weeds can be. They thrive on the very same things your garden does: sunlight, water, and nutrients in the soil. Weeds take pretty much any opportunity to grow and aren’t picky about where they take root. As plant-based mulch decomposes, it provides an attractive, nutrient-rich environment for weeds to take root.
We often find weed seeds in old or contaminated mulch. Seeds can also get distributed by birds or wind into new beds.
What’s the Best Mulch to Prevent Weeds?
Here are a few strategies for preventing weeds from popping up in your mulch:
For flower beds and landscaping, we like a chipped or shredded bark mulch with a relatively coarse texture. It decomposes relatively slowly and doesn’t blow away so it can do its job and keep sunlight from reaching the soil. Inorganic mulch (like stones or gravel) does an excellent job of preventing weed growth. However, it doesn’t offer the soil-improving benefits of organic mulch.
As experienced gardeners know, fighting weeds is a never-ending battle. They seem to pop up no matter what you do. But there are proven strategies for preventing them, and mulch is one of the best tools available. Working with a professional for your landscaping needs, including mulch application, is the best way to make sure your weed control program works.
Why Do Weeds Grow In Mulch?
Applying mulch every spring makes sense on several levels. It helps enrich the soil and helps retain moisture during the dry summer months. But the main reason most of us mulch is weed control. We faithfully lay down a couple of inches of mulch and cross our fingers that we’ve won the battle. But most of us aren’t so lucky: weeds almost always find a way to pop up, even in the most beautifully mulched landscaping. Why are weeds so hard to tame, and what can you do to stop them? Here are a few tips:
At Epling, our experienced team knows which type of mulch to use in different locations. We apply just the right amount for each job, both for weed control and curb appeal. We have herbicide use down to a science and know which kind to use, both before and after mulching. This spring, put the focus on spending time outdoors with family and let our pros at Epling take care of the weeds.